diff --git a/configure.ac b/configure.ac
index 161ff00..64391b4 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-AC_PREREQ(2.52)
+AC_PREREQ(2.64)
 
 # Process this file with autoconf to produce a configure script.
 AC_INIT([json-c], 0.12.99, [json-c@googlegroups.com])